Strange Lighting behaviour
 

Hello,

I'm hoping you can give some advice.

We recently moved into a 3 year old house. After a few days we noticed
something odd with the lights. Basically unless the downstairs hall light
is switched on, the lounge and dining room lights will not function.

I'm just trying to decide what to do. If it is going to be complicated to
fix then I think I'll just live with it as a "feature".

TIA

Steve.

Strange Lighting behaviour
 

Most likely is that the lounge and dining room are looped into the switched
live rather than permanent live at the hall light.

Assuming it is a standard pendent fitting, do the following:

1. Remove bulb and shade from hall light.
2. Unscrew rose.
3. Examine the wiring. There should be:

a) A flex to the bulb holder.
b) A cable to the switch (should be identified by having red tape or
sleeving on its black wire).
c) A number of other cables, probably 2.

All the earths from these cables should go to an earth terminal.

The other terminals are usually in a row, with the following layout.

Switched live should consist of a terminal block with 2 holes for bulb and
switch. One should go to the brown wire to the bulb holder. The other should
be one of the switch wires.

In the middle should be a terminal with permanent live. There are normally 3
holes, for feed in, feed out, and switch feed. The other switch cable
(usually the genuine red one) goes here, along with every other red wire
(usually an extra 2).

On the other side should be the neutral block, with again should have 3
holes for feed in, feed out and bulb. The blue from the lamp holder plus all
the black wires (except the red taped line from the switch) should go here.

If there are any discrepancies, this might be your problem. In particular,
you should ensure that the brown wire goes to the outside terminal along
with only one other wire.

Christian.

Strange Lighting behaviour
 

"Steve" wrote in message
...
Hello,

I'm hoping you can give some advice.

We recently moved into a 3 year old house. After a few days we noticed
something odd with the lights. Basically unless the downstairs hall light
is switched on, the lounge and dining room lights will not function.

I'm just trying to decide what to do. If it is going to be complicated to
fix then I think I'll just live with it as a "feature".

TIA

Steve.

First guess is that when the electrician (or whatever) wired on from the
hall light to the lounge lights, instead of extending the power circuit s/he
took the power for the lounge off the switch circuit for the hall.

Not an impossible mistake to make.
Lighting is usually four sets of wires.

1) Power in.
2) Power out.
{These share the same terminals}
3) Live to switch and back (goes on the red wire comes back on the black
wire).
4) 'Switch return' to light (red joined to black above) and neutral to light
(black joins neutral on power circuit)

All the earths should also join :-)

There are two main ways of wiring lighting:
(1) All the wires into a ceiling rose
(2) Junction box between floors/in loft.

So if you can find the junction e.g. in ceiling rose it is straighforward to
fix.
If the circuit has been wired through junction boxes you may have to lift
the bedroom or landing floor to get at the wiring.

In either case you need a meter to check which wires are live all the time
and which are only live when the switch in on.

Of more concern s that you have faulty wiring.
If there is one fault there may be more.
It could be wise to have the whole house safety checked by a qualified
electrician.

If the house has dodgy wiring then you may have some comeback on the
vendors; if the house is only 3 years old you may have a claim under any
warranty which came with the house (assuming the fault is original and not
due to hacking by the previous owner).

It could be as simple as someone replacing the hall light and conecting the
new light up wrongly.
On the other hand........

HTH
Dave R

Strange Lighting behaviour
 

Sounds like the loop in (supply) for your lounge/dining room is comming from
the flex connection in your hall, rather than the loop in for that one.

Inside a typical ceiling rose you have 4 sets of connectors: a loop in, a
flex , a neutral and earth. The loop in is permanently connected to live
(via the loop in on the previous light in the circuit), the neutral is
permanently connected to neutral. The switch goes between loop in and flex,
the light itself goes between flex and neutral.
The supply to the next light should be taken from the loop in connector,
NOT the flex.

That or there's some other problem ;-

Bax

Strange Lighting behaviour
 

"Steve" wrote:

Hello Steve

S| We recently moved into a 3 year old house. After a few days
S| we noticed something odd with the lights. Basically unless
S| the downstairs hall light is switched on, the lounge and
S| dining room lights will not function.

Amazing.

S| I'm just trying to decide what to do. If it is going to be
S| complicated to fix then I think I'll just live with it as a
S| "feature".

Whoever wired the lounge and dining room lights obviously mistook the
switched live from the hall circuit as permanent live and wired from
that.

It's bad and implies the wiring was done by somebody bereft of clue.
Suggest you get a competent electrician in to check for other
"features".

To actually fix, you can move the feed for those rooms onto a
*permanent* live on the lighting circuit, having checked it's capable
of the load.

--
Simon Avery, Dartmoor, UK
uk.d-i-y FAQ: http://www.diyfaq.org.uk/